1. Field of the Invention
The invention relates to the field of devices for processing optical signals and more particularly to resource (or optical signal) routing devices.
2. Description of the Prior Art
Optical communication networks generally comprise optical nodes, for example optical add/drop multiplexers (OADM), provided with a processing device for routing (or switching) resources to another node or to terminals or servers.
To this end, the processing devices generally comprise supply means adapted to deliver optical signals, multiplexing means adapted to deliver to at least one primary port a multiplex of channels corresponding to chosen bandwidths and comprising optical signals received at secondary ports, and optical routing means adapted, as a function of instructions received, to route the optical signals delivered by the supply means selectively to second ports of the first multiplexing means.
In the present context, “multiplexing means” means unidirectional multiplexers, unidirectional demultiplexers and bidirectional multiplexers/demultiplexers. Also, “primary port” means an input and/or an output of multiplexer means adapted to deliver and/or to receive a multiplex. Also, “secondary port” means an input and/or an output of multiplexer means adapted to deliver and/or to receive optical signals that are not multiplexed.
For the optical nodes to be (re)configurable, the supply means of their processing device comprise sources consist of lasers whose wavelength may be tuned. These tunable lasers require control devices for controlling their output wavelength by feedback, and this considerably increases the cost of the sources.
Thus an object of the invention is to remedy this problem.